OAI/Geometry/EinsteinFour/JacobiRadialODE.lean

GitHub source file

4 declarations, 0 contain sorry, 0 declared as axioms

Radial determinant comparison from the Jacobi ODE.

  1. def OAI.PositiveEinsteinFour.Jacobi.radialCurvature line 14
  2. theorem OAI.PositiveEinsteinFour.Jacobi.sampled_radialCurvature line 16
  3. theorem OAI.PositiveEinsteinFour.Jacobi.RegularJacobi.radial_determinant_comparison line 33

    Source documentation

    The Jacobi radial inequality follows from the ODE, trace normalization, and preconjugacy.

    theorem radial_determinant_comparison (ht : 0 < t) (htπ : t < Real.pi)
        (hpre : ∀ s, 0 < s → s ≤ t → IsUnit (d.J s))
        (htrace : ∀ s, (d.R s).trace = 3)
        {L : ℝ} (hL : 0 ≤ L)
        (hc : Continuous (fun s => Averages.sineWeight s • radialCurvature d.R t s))
        (hLip : ∀ s r,
          ‖Averages.sineWeight s • radialCurvature d.R t s -
            Averages.sineWeight r • radialCurvature d.R t r‖ ≤ L * |s - r|) :
        (d.J t).det ≤ Real.sin t ^ 3 * ((1 : NormalMatrix) -
          (t ^ 2 / (Real.pi ^ 2 - t ^ 2)) •
            (∫ s in (0 : ℝ)..1, Averages.sineWeight s • radialCurvature d.R t s)).det := by
    …

    Mentions: OAI.PositiveEinsteinFour.Averages.sineWeight, OAI.PositiveEinsteinFour.Jacobi.radialCurvature, OAI.PositiveEinsteinFour.Jacobi.NormalMatrix

  4. theorem OAI.PositiveEinsteinFour.Jacobi.RegularJacobi.radial_compression_posSemidef line 52

    Source documentation

    The limiting compression is positive semidefinite, including a singular limit; this is the spectral input for the subsequent determinant deficit.

    theorem radial_compression_posSemidef (ht : 0 < t) (htπ : t < Real.pi)
        (hpre : ∀ s, 0 < s → s ≤ t → IsUnit (d.J s))
        {L : ℝ} (hL : 0 ≤ L)
        (hc : Continuous (fun s => Averages.sineWeight s • radialCurvature d.R t s))
        (hLip : ∀ s r,
          ‖Averages.sineWeight s • radialCurvature d.R t s -
            Averages.sineWeight r • radialCurvature d.R t r‖ ≤ L * |s - r|) :
        ((1 : NormalMatrix) - (t ^ 2 / (Real.pi ^ 2 - t ^ 2)) •
          (∫ s in (0 : ℝ)..1, Averages.sineWeight s • radialCurvature d.R t s)).PosSemidef := by
    …

    Mentions: OAI.PositiveEinsteinFour.Averages.sineWeight, OAI.PositiveEinsteinFour.Jacobi.radialCurvature, OAI.PositiveEinsteinFour.Jacobi.NormalMatrix